This show gets a bad rap. Sure it's American-made wannabe anime, but it's American-made wannabe anime with decent writing and continuity.
The grammar could be better. You don't usually need a comma before "because," for instance. You don't need to capitalize the "the" in "The Titans" unless it starts a sentence.
"Fought with us instead of her?" I don't see Beast Boy fighting against the other Titans in any case. At most, he'd use his powers to try to break up the fight, but he'd never attack.
Poignant, but the ending could be stronger.